Napa Valley Cabernet Sauvignon Hang Time Study Ed Weber Viticulture Farm Advisor UC Cooperative Extension Napa County
Changing perspectives on when to pick Cabernet Sauvignon Winemakers are waiting for green characters to go away and/or for changes in phenolic characters In much of Napa Valley, Brix levels have become irrelevant for deciding when to pick Cabernet Sauvignon Water additions Alcohol removal
Weighted Ave. Brix Napa County Cabernet Sauvignon 26.0 25.5 25.0 24.5 24.0 23.5 23.0 22.5 22.0 Data from Grape Crush Report
Why Study Hang Time? Growers experienced crop losses and lower economic returns in 2003 & 2004 with extended hang time Grapes lose weight with extended hang time, but there is little data documenting crop losses Interest and support from grower organizations statewide
What We Did Established small plots in 2005 in 5 Napa Valley Cabernet Sauvignon vineyards Harvested grapes and measured yield and juice parameters over a 7-week harvest period in 2005 and 2006 Made wines
Who Helped? Mike Anderson & Jason Benz UCD Viticulture & Enology Napa Valley Grapegrowers Cooperating vineyards Labor providers: Beckstoffer Vineyards Duckhorn Vineyards Silverado Farming Company Vista Vineyard Management Bins & Pans: Duckhorn Vineyards Mumm Napa Valley
Who Helped? Analytical work ETS Laboratories Gordon Burns & Steve Price Barrels & Racks Miner Family Winery Gary Brookman Facilities UCD Oakville Experimental Vineyard
Our Vineyards Vineyard Location Clone Rootstock Spacing Trellis Year Planted 1 Oak/Ruth 337 039-16 7 x 8 VSP 1994 2 Oak/Ruth 4 110R 5 x 6 VSP 1994 3 Oak/Ruth 337 101-14 5 x 6 VSP 1996 4 Oak/Ruth 7 039-16 8 x 8 VSP 1996 5 Calistoga 337 110R 5 x 7 VSP 1997
Plot Design at Each Site Rep 3 vines 3 vines 3 vines 3 vines 3 vines 3 vines 3 vines 1 Red Orange White Yellow Green Blue Pink 2 Green Pink White Blue Orange Red Yellow 3 Blue White Green Pink Yellow Orange Red 4 Pink Yellow Orange Red Green Blue White 5 Yellow White Blue Pink Orange Red Green Harvest #1 Harvest #2 Harvest #3 Harvest #4 Harvest #5 Harvest #6 Harvest #7 White Blue Red Green Orange Pink Yellow
Brix 2005 Brix Levels 31 30 29 28 27 26 25 24 23 22 1 2 3 4 5 6 7 Sept. 20 Week Nov. 1 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5
Brix 2005 Brix Levels 31 30 29 28 27 26 25 24 23 22 1 2 3 4 5 6 7 Sept. 20 Week Nov. 1 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5
Brix 2006 Brix Levels 31 30 29 28 27 26 25 24 23 22 1 2 3 4 5 6 7 Sept. 19 Week Oct. 31 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5
% Brix 2006 Brix Levels 31 30 29 28 27 26 25 24 23 22 1 2 3 4 5 6 7 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 Sugar accumulation or dehydration? Week 2006 Moisture Content 76 74 72 Vyd 1 Vyd 2 70 68 66 Vyd 3 Vyd 4 Vyd 5 64 1 2 3 4 5 6 7 Week
% Brix 2005 Brix Levels 31 30 29 28 27 26 25 24 23 22 1 2 3 4 5 6 7 Week Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 2005 Moisture Content 76 2005 74 72 70 68 66 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 64 1 2 3 4 5 6 7 Week
% Brix Sugar Accumulation Berries accumulate sugar up to 23-25 Brix Dehydration may occur at the same time 31 30 29 28 27 26 25 24 23 22 2006 Brix Levels 1 2 3 4 5 6 7 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 Above 25-26, higher Brix levels occur due to dehydration 76 Week 2006 Moisture Content 74 72 70 68 66 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 64 1 2 3 4 5 6 7 Week
Cluster weight (lb) 2005 Cluster Weight Reductions 0.55 0.5 0.45 0.4 0.35 0.3 0.25 22 23 24 25 26 27 Brix Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 Vyd 1 2 3 4 5 r 2.12.54.61.75.43
Cluster weight (lb) 2006 Cluster Weight Reductions 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 23 25 27 29 31 Brix Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 Vyd 1 2 3 4 5 r 2.85.69.53.81.89
Cluster weight (lb) Cluster Weight Reduction Per Degree Brix 2006 Cluster Weight Reductions 2005 2006 Vyd 1 1% 6% 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 Vyd 2 5% 5% 23 25 27 29 31 Brix Vyd 3 4% 5% Vyd 4 4% 4% Vyd 5 6% 10%
Cluster Weight Reduction Per Degree Brix 2005 2006 Vyd 1 1% 6% Vyd 2 5% 5% Vyd 3 4% 5% Vyd 4 4% 4% 5% appears to be a reasonable estimate for cluster weight reductions per degree Brix above 26. Vyd 5 6% 10%
Lbs Lbs 2005 Cluster weights 0.60 0.50 0.40 0.30 0.20 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 0.10 1 2 3 4 5 6 7 Week 2006 Cluster weights Ave Brix: 24.2 24.4 0.50 0.40 0.30 Vyd 1 Vyd 2 Vyd 3 Vyd 4 0.20 Vyd 5 0.10 1 2 3 4 5 6 7 Week
Changes in Cluster Weights 4 weeks Hang time Vyd 1 + 3.7% 2005 2006 Vyd 2-3.6% - 16.1% Vyd 3-0.5% - 8.7% Vyd 4-3.4% - 16.4% Vyd 5-14.3% - 10.9%
2005 Clusters per vine 60 50 40 30 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 20 1 2 3 4 5 6 7 Week 2006 Clusters per vine 60 50 40 30 Vyd 1 Vyd 2 Vyd 3 Vyd 4 Vyd 5 20 1 2 3 4 5 6 7 Week
Yield Reductions 4 weeks Hang time Cluster Wt. 2005 2006 Yield per acre Vyd 1 + 3.7% + 7.4% Cluster Wt. Yield per acre Vyd 2-3.6% - 10.0% - 16.1% - 17.2 Vyd 3-0.5% - 6.9% - 8.7% - 14.3 Vyd 4-3.4% - 13.9% - 16.4% - 13.2 Vyd 5-14.3% - 15.4% - 10.9% - 21.3
2005 Wine Analyses Courtesy of ETS Laboratories Week EtOH ph TA 1 13.28 3.82 0.50 2 13.47 3.81 0.50 3 14.01 3.86 0.54 4 14.66 3.94 0.52 5 15.40 3.96 0.53 6 14.86 3.96 0.48 7 15.03 4.01 0.49
Hang Time Summary Brix levels reached a natural plateau at 25-26 Brix in both years Increased Brix above 25-26 were due to dehydration Measuring moisture content may be a useful tool to detect dehydration effects Yield losses due to dehydration may be estimated at 5% per degree Brix above 26
Beyond Hang Time Is Hang Time a passing fad? There are many wineries harvesting grapes at 23-24 Brix and making exceptional wines. Will new contract language fix the Hang Time controversy? Yields go down with extended hang times. Should growers be paid more for higher Brix fruit?
Napa County Cabernet Sauvignon Wt d Ave. Brix 26.0 25.5 25.0 24.5 24.0 23.5 23.0 22.5 22.0 Wt d Ave. $/ton 4,500 4,000 3,500 3,000 2,500 2,000 1,500 1,000 500 0 Data from Grape Crush Report
Beyond Hang Time Ultimately, the solution to the Hang Time Controversy is building good relationships between wineries and growers and agreement about the importance of wine quality Sugar accumulation versus dehydration research won t settle the debate A way to measure potential wine quality would be a big help
Napa Valley Cabernet Sauvignon Hang Time Study Ed Weber Viticulture Farm Advisor http://cenapa.ucdavis.edu